Structures and Optical Properties of Nanoforest-Like Carbon Nanotubes Decorated with Nanoparticles of Strontium Aluminate Doped with Rare-Earth Elements

MRS Advances ◽  
2018 ◽  
Vol 3 (1-2) ◽  
pp. 121-126
Author(s):  
Patsy Y. Arquieta Guillén ◽  
Alena Borisovna Kharissova ◽  
Beatriz Ortega García ◽  
Oxana V. Kharissova
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Metal Oxides ◽  
Spray Pyrolysis ◽  
Metal Oxide Nanoparticles ◽  
Strontium Aluminate ◽  
Fluorescent Properties ◽  
Multi Wall Carbon Nanotubes

ABSTRACTNowadays, carbon nanotubes have a lot of applications in daily life, being applied in the fabrication of cellphones, computers, nanotransistors, among many others. Currently, their new applications in biotechnology area are in research, in particular in order to find new biosensors with fluorescent properties applying on the basis of multi-wall carbon nanotubes (MWCNTs). In this work, the obtaining of carbon nanoparticles having fluorescent properties via spray pyrolysis is presented. Synthesis, properties, structural peculiarities, and applications of nanobuds and related nanostructures are discussed. MWCNTs, decorated with strontium aluminate SrAl12O19 and doped with rare-earth elements, were synthetized from distinct organic precursors and the corresponding metal oxides. The metal oxides used were Samarium (Sm), Europium (Eu), Neodymium (Nd), Lanthanum (La), Cerium (Ce) and some their combinations.The synthesis was carried out on the surface of optical fibres to obtain a uniform growth of forest-like MWCNTs, adding to metal oxide nanoparticles to their surface. The preparation of composites was carried out by spray pyrolysis techniques in dry nitrogen atmosphere in the temperature range from 780 to 850°C. The formed products were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), FTIR spectroscopy, Raman spectroscopy and UV/visible spectroscopies. The analysis of the obtained data shows that the deposited nanoparticles are in the range of size 20-60 nm being uniformly distributed on the surface of MWCNTs. The samples, obtained at different temperatures and with doping metal oxides added to SrAl12O19, show different fluorescence behavior. The best results were observed with lanthanum oxide as a dopant. Possible applications as persistently luminescent phosphors for the formed MWCNTs-supported luminescent materials are proposed.

Synthesis and Study of Fluorescent Forest-like Carbon Nanotubes Doped with Oxides of Rare-earth Elements

2019 ◽  
Vol 4 (1) ◽  
pp. 39-50
Author(s):  
Patsy Y.A. Guillén ◽  
Oxana V. Kharissova ◽  
Romeo Selvas ◽  
Boris I. Kharisov
Keyword(s):  
Carbon Nanotubes ◽  
Spray Pyrolysis ◽  
Rare Earths ◽  
Spray Pyrolysis Technique ◽  
Spray Pyrolysis Method ◽  
Catalyst Precursor ◽  
Strontium Aluminate ◽  
Fluorescent Properties ◽  
Lanthanide Oxides ◽  
Pyrolysis Method

Background: Methods for obtaining the hybrids of multi-wall carbon nanotubes (MWCNTs) and rare earths are in progress. Such composites may possess luminescent properties, which could be of interest for various areas, in particular, medicine (imaging), engineering (fluorescent polymers, LED and relative materials), among other applications. Lanthanide oxides, additionally, can serve as catalysts for MWCNTs formation and catalysts of several organic reactions. Objective: The goal of this work is to obtain the composites of MWCNTs with strontium aluminate, doped with several lanthanides (Eu, Ce, La, Nd, and Sm), via the spray pyrolysis method and to study the properties of the formed hybrids. Methods: The spray pyrolysis method in the temperature range from 780 to 850oC, starting from toluene as a carbon source and ferrocene as a catalyst precursor. SrAl12O19 doped with rare-earths were added to carbon matter in the ultrasonic field. Methods: Among various structures, the forest-like nanostructures have been observed in some cases. The formed coated carbon nanotubes possess fluorescent properties due to the attachment of lanthanide- doped ceramic compound (SrAl12O19) to their surface, allowing the emission control for each dopant: yellow (Nd2O3), blue (Eu2O3 and Sm2O3), intense orange (La2O3), light orange (Ce2O3). Conclusion: MWCNTs decorated with strontium aluminate (SrAl12O19), doped with a series of lanthanide oxides (Nd2O3, Eu2O3, La2O3, Ce2O3, Sm2O3), were obtained by the spray pyrolysis technique on the surface of optical fibers. Lanthanum- and cerium-containing coatings were found to show a better deposition on the MWCNTs surface, exhibiting uniform coating. MWCNTs, coated with Nd-, Ce-, and Eu-doped SrAl12O19 were shown to reveal the best conductive properties.

Growth of Multi-Walled Carbon Nanotubes by Nebulized Spray Pyrolysis of a Natural Precursor: Alpha-Pinene

2008 ◽  
Vol 8 (12) ◽  
pp. 6509-6512 ◽  
Author(s):  
J. Lara-Romero ◽  
G. Alonso-Núñez ◽  
S. Jiménez-Sandoval ◽  
M. Avalos-Borja
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Raman Spectroscopy ◽  
Spray Pyrolysis ◽  
Iron Carbide ◽  
Multi Wall Carbon Nanotubes ◽  
Alpha Pinene ◽  
Transmission Electron ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Multi-wall carbon nanotubes (MWCNT) were prepared by spray-pyrolysis of alpha-pinene, a botanical hydrocarbon, and ferrocene as catalyst at 900 °C. The MWCNT were analyzed by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. The microscopy studies show the formation of carbon nanotubes with diameters between 20 and 30 nm and length greater than one hundred microns. Nanoparticles were detected outside and inside the nanotubes and were identify as metallic iron and iron carbide, respectively. Raman spectroscopy reveals that the alpha-pinene grown carbon nanotubes are graphitized showing both the D and G bands at 1335 cm−1 and 1585 cm−1 respectively.

scholarly journals Phytosynthetic Fabrication of Lanthanum Ion-Doped Nickel Oxide Nanoparticles Using Sesbania grandiflora Leaf Extract and Their Anti-Microbial Properties

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 124
Author(s):  
Srihasam Saiganesh ◽  
Thyagarajan Krishnan ◽  
Golla Narasimha ◽  
Hesham S. Almoallim ◽  
Sulaiman Ali Alhari ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Optical Properties ◽  
Rare Earth ◽  
Nickel Oxide ◽  
Photoelectron Spectroscopy ◽  
Metal Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Nio Nanoparticles ◽  
X Ray ◽  
Sesbania Grandiflora

Over the past few years, the photogenic fabrication of metal oxide nanoparticles has attracted considerable attention, owing to the simple, eco-friendly, and non-toxic procedure. Herein, we fabricated NiO nanoparticles and altered their optical properties by doping with a rare earth element (lanthanum) using Sesbania grandiflora broth for antibacterial applications. The doping of lanthanum with NiO was systematically studied. The optical properties of the prepared nanomaterials were investigated through UV-Vis diffuse reflectance spectra (UV-DRS) analysis, and their structures were studied using X-ray diffraction analysis. The morphological features of the prepared nanomaterials were examined by scanning electron microscopy and transmission electron microscopy, their elemental structure was analyzed by energy-dispersive X-ray spectral analysis, and their oxidation states were analyzed by X-ray photoelectron spectroscopy. Furthermore, the antibacterial action of NiO and La-doped NiO nanoparticles was studied by the zone of inhibition method for Gram-negative and Gram-positive bacterial strains such as Escherichia coli and Bacillus sublitis. It was evident from the obtained results that the optimized compound NiOLa-04 performed better than the other prepared compounds. To the best of our knowledge, this is the first report on the phytosynthetic fabrication of rare-earth ion Lanthanum (La3+)-doped Nickel Oxide (NiO) nanoparticles and their anti-microbial studies.

scholarly journals Degradation Behavior, Transport Mechanism and Osteogenic Activity of Mg–Zn–RE Alloy Membranes in Critical-Sized Rat Calvarial Defects

Coatings ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 496
Author(s):  
Mingyu Zhao ◽  
Guanqi Liu ◽  
Ying Li ◽  
Xiaodong Yu ◽  
Shenpo Yuan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Transport Mechanism ◽  
Degradation Process ◽  
Lymph System ◽  
Transmission Electron ◽  
Calvarial Defects ◽  
Rat Calvarial Defect

In this study, a specific Mg–Zn–RE alloy membrane with 6 wt.% zinc and 2.7 wt.% rare earth elements (Y, Gd, La and Ce) was prepared to investigate implant degradation, transport mechanism and guide bone regeneration in vivo. The Mg-membrane microstructure and precipitates were characterized by the scanning electron microscopy (SEM) and the transmission electron microscopy (TEM). The Mg-membrane degradation process and effect on osteogenesis were investigated in a critical-sized rat calvarial defect model via micro-CT examination and hard tissue slicing after 2-, 5- and 8-week implants. Then, the distribution of elements in organs after 1-, 2- and 4-weeks implantation was examined to explore their transportation routes. Results showed that two types of precipitates had formed in the Mg–membrane after a 10-h heat treatment at 175 °C: γ-phase MgZn precipitation with dissolved La, Ce and Gd, and W-phase Mg3(Y, Gd)2Zn3 precipitation rich in Y and Gd. In the degradation process of the Mg-membrane, the Mg matrix degraded first, and the rare earth-rich precipitation particles were transferred to a more stable phosphate compound. The element release rate was dependent on the precipitate type and composition. Rare earth elements may be transported mainly through the lymph system. The defects were repaired rapidly by the membranes. The Mg-membrane used in the present study showed excellent biocompatibility and enhanced bone formation in the vicinity of the implants.

scholarly journals Gas Sensing with Iridium Oxide Nanoparticle Decorated Carbon Nanotubes

Sensors ◽  
2018 ◽  
Vol 19 (1) ◽  
pp. 113 ◽  
Author(s):  
Juan Casanova-Cháfer ◽  
Eric Navarrete ◽  
Xavier Noirfalise ◽  
Polona Umek ◽  
Carla Bittencourt ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Gas Sensing ◽  
Metal Oxide Nanoparticles ◽  
Iridium Oxide ◽  
Oxide Nanoparticles ◽  
Step Method ◽  
Experimental Conditions ◽  
Multi Wall Carbon Nanotubes ◽  
Condensation Growth ◽  
Oxide Nanoparticle

The properties of multi-wall carbon nanotubes decorated with iridium oxide nanoparticles (IrOx-MWCNTs) are studied to detect harmful gases such as nitrogen dioxide and ammonia. IrOx nanoparticles were synthetized using a two-step method, based on a hydrolysis and acid condensation growth mechanism. The metal oxide nanoparticles obtained were employed for decorating the sidewalls of carbon nanotubes. Iridium-oxide nanoparticle decorated carbon nanotube material showed higher and more stable responses towards NH3 and NO2 than bare carbon nanotubes under different experimental conditions, establishing the optimal operating temperatures and estimating the limits of detection and quantification. Furthermore, the nanomaterials employed were studied using different morphological and compositional characterization techniques and a gas sensing mechanism is proposed.

Ultrasound promoted green oxidation of alkenes with hydrogen peroxide in the presence of iron porphyrins supported on multi-walled carbon nanotubes

2015 ◽  
Vol 19 (04) ◽  
pp. 622-630 ◽  
Author(s):  
Saeed Rayati ◽  
Zahra Sheybanifard
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Hydrogen Peroxide ◽  
Heterogeneous Catalyst ◽  
Multi Wall Carbon Nanotubes ◽  
Mechanical Stirring ◽  
Transmission Electron ◽  
Multi Walled Carbon Nanotubes ◽  
Ft Ir ◽  
Walled Carbon Nanotubes

In the present work, oxidation of alkenes with hydrogen peroxide in the presence of meso-tetrakis(4-hydroxyphenyl)porphyrinatoiron(III) chloride supported onto surface of functionalized multi-wall carbon nanotubes (FMWCNT), [ Fe ( THPP ) Cl@MWCNT ], is reported. The simple heterogeneous catalyst was characterized by FT-IR spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and also thermal analysis. The amount of the catalyst loaded on the nanotubes was determined by atomic absorption spectroscopy. This heterogeneous catalyst proved to be an efficient and green catalyst and was successfully able to activate hydrogen peroxide without any additive toward the oxidation of alkenes in ethanol as a green solvent. Performance of the catalyst in oxidation of various alkenes was inspected under reflux, ultrasonic irradiation and mechanical stirring. Moreover, the catalyst can be reused several times under similar conditions.

scholarly journals Recent Trends in the Microwave-Assisted Synthesis of Metal Oxide Nanoparticles Supported on Carbon Nanotubes and Their Applications

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Sarah C. Motshekga ◽  
Sreejarani K. Pillai ◽  
Suprakas Sinha Ray ◽  
Kalala Jalama ◽  
Rui. W. M. Krause
Keyword(s):  
Carbon Nanotubes ◽  
Metal Oxides ◽  
Chemical Reduction ◽  
Metal Oxide Nanoparticles ◽  
Power Input ◽  
Metal Nanoparticle ◽  
Microwave Assisted Synthesis ◽  
Microwave Assisted ◽  
Coated Metal ◽  
Size And Morphology

The study of coating carbon nanotubes with metal/oxides nanoparticles is now becoming a promising and challenging area of research. To optimize the use of carbon nanotubes in various applications, it is necessary to attach functional groups or other nanostructures to their surface. The combination of the distinctive properties of carbon nanotubes and metal/oxides is expected to be applied in field emission displays, nanoelectronic devices, novel catalysts, and polymer or ceramic reinforcement. The synthesis of these composites is still largely based on conventional techniques, such as wet impregnation followed by chemical reduction of the metal nanoparticle precursors. These techniques based on thermal heating can be time consuming and often lack control of particle size and morphology. Hence, there is interest in microwave technology recently, where using microwaves represents an alternative way of power input into chemical reactions through dielectric heating. This paper covers the synthesis and applications of carbon-nanotube-coated metal/oxides nanoparticles prepared by a microwave-assisted method. The reviewed studies show that the microwave-assisted synthesis of the composites allows processes to be completed within a shorter reaction time with uniform and well-dispersed nanoparticle formation.

Aligned Carbon Nanotubes Via Microwave Plasma Enhanced Chemical Vapor Deposition

1999 ◽  
Vol 593 ◽  
Author(s):  
H. Cui ◽  
D. Palmer ◽  
O. Zhou ◽  
B. R. Stoner
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Silicon Substrates ◽  
Multi Wall Carbon Nanotubes ◽  
Field Emission Properties ◽  
Transmission Electron

ABSTRACTAligned multi-wall carbon nanotubes have been grown on silicon substrates by microwave plasma enhanced chemical vapor deposition using methane/ammonia mixtures. The concentration ratio of methane/ammonia in addition to substrate temperature was varied. The morphology, structure and alignment of carbon nanotubes were studied by scanning electron microscopy and transmission electron microscopy. Both concentric hollow and bamboo-type multi-wall carbon nanotubes were observed. Growth rate, size distribution, alignment, morphology, and structure of carbon nanotubes changed with methane/ammonia ratio and growth temperature. Preliminary results on field emission properties are also presented.

Uptake of rare earth elements from solution by metal oxides

1993 ◽  
Vol 27 (9) ◽  
pp. 1796-1802 ◽  
Author(s):  
Dirk Koeppenkastrop ◽  
Eric H. De Carlo
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Metal Oxides
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